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downwind
28th Apr 2020, 12:21
Hello All,

Reading FCOM and QRH, I came across a confusing statement regarding non-normal checklist/DDG application.

In the QRH Checklist Instructions, Non–Normal Checklist Operation section this procedure is written;

"If an amber caution light illuminates during MASTER CAUTION recall, but extinguishes after MASTER CAUTION reset, completion of the associated checklist is not required."

However in the FCOM, Normal Procedures, Configuration Check section, it states;

"If, during recall, an amber caution illuminates and then extinguishes after a master caution reset:

• check the DDG or the operator equivalent"

As can been seen in the QRH it makes no mention to check the DDG after a master caution reset, however the FCOM it requires you to check the DDG?

I am confused on these procedural requirements, can someone please clarify or have I interpreted the situation incorrectly?

Finally in the FCTM, Preface Introduction General, it states;

“Note: In the event of a conflict, the procedures and restrictions published in the FCOM, QRH, MMEL/MEL, or DDG take precedence over the information, techniques, and recommendations in the FCTM.”

Thank You

FlyingStone
28th Apr 2020, 13:57
FCOM requires you to check the DDG, so that's what would be prudent to do. Surely the alternative (not checking anything) is not the best idea?

Banana Joe
28th Apr 2020, 14:25
I don't know the MEL/DDG by heart to remember which single channel faults can affect dispatch for the next sector, but if any does then it's good to know. You might be going to a regional destination where you have no tech support and you would be stuck there. It's better to get the info you need and make an informed diversion.

I once experienced a pressurization controller fault during the descent into an airport where we had no maintenance support and we diverted to our main base. Had we landed, we would have been stuck there for the night.

AerocatS2A
28th Apr 2020, 15:28
There is no conflict. The QRH says there’s no need to do the emergency checklist and makes no mention of checking the DDG, presumably because that is beyond the scope of the QRH. The FCOM says to check the DDG because the FCOM is taking a broader operational view.